Modern consumer electronics, such as smart phones, personal digital assistants, and location based services devices, as well as enterprise electronics, such as servers and storage arrays, are packing more integrated circuits into an ever shrinking physical space with expectations for decreasing cost. Contemporary electronics expose integrated circuits and packages to more demanding and sometimes new environmental conditions, such as cold, heat, and humidity. As more functions are packed into the integrated circuits and more integrated circuits into the package, more heat is generated degrading the performance, the reliability, and the lifetime of the integrated circuits.
Every new generation of integrated circuits with increased operating frequency, performance and the higher level of large scale integration have underscored the need for robust thermal management structures with integrated circuit packages. It is well acknowledged that when a semiconductor device becomes denser in term of electrical power consumption per unit volume, heat generated is also increases correspondingly. As the state of the art progresses, the ability to adequately dissipate heat is often a constraint on the rising complexity of package architecture design, smaller footprint, higher device operating speed and power consumption. Numerous technologies have been developed to meet these requirements. Some of the research and development strategies focus on new thermal package technologies while others focus on improving the existing package technologies. Yet others focus on wafer level chip scale packaging to minimize packaging process complexity and package dimensions.
Wafer level chip scale package (WLCSP), unlike any conventional packages, is a bumped die that can be directly mounted on a printed circuit board (PCB) without requiring further packaging. This package type offers a cheaper alternative compared to conventional chip scale package (CSP). Typical WLCSP does not have any thermal conductive medium on its back surface providing the only possible way to conduct the heat generated from the package itself is through the solder bumps on the active side of the WLCSP. This limits the use of such packages to slow speed, low powered applications. Other approaches attach thermally conductive materials to the back surface of the wafer but require additional processing steps of the wafer before thermal attachment, increase cost, and present control difficulty.
Thus, a need still remains for a stackable integrated circuit package system providing low cost manufacturing, improved yields, reduction of the integrated circuit package dimensions, and flexible stacking and integration configurations. In view of the ever-increasing need to save costs and improve efficiencies, it is more and more critical that answers be found to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.